Tripping sling apparatus



June 25, 1968 c. E. ESTES 3,389,933

TRIPPING SLING APPARATUS I Filed April '21. 1967 2 Sheets-Sheet 1 INENTOR. CLANCY E. ESTES BY 6 lawn:

June 25, 1968 c. E. ESTES 3,339,933

TRIPPING SLING APPARATUS Filed April 21, 1967 2 Sheets-Sheet 2 I 145 g H14 59 H 1 157 United States Patent 3,389,933 TRIPPING SLING APPARATUS Clancy E. Estes, Louisville, Miss., assignor to Taylor Machine Works, Louisville, Miss. Filed Apr. 21, 1967, Ser. No. 632,756 6 Claims. (Cl. 294-76) ABSTRACT OF THE DISCLOSURE Tripping sling apparatus for handling pulpwood logs or the like and for use with vehicular lifting means having an elevatable carriage or for use with tension line, crane or trolley overhead lifting means. The apparatus includes four sling halves connectable in pairs to make two full slings parallel spaced apart. A sling half is adapted to be disconnectably connected with one of two other sling halves thereby optionally forming a parallel spaced pair of full slings extending in one direction or for forming a pair of slings extending in a direction perpendicularly thereto. The sling halves are Optionally adapted to be connected together to form a short-spaced parallel pair of full slings or to form a long-spaced parallel pair of full slings; the parallel pair of full slings are adapted to be arranged a short distance apart for handling short loads or adapted to be arranged a relative long distance apart for handling long loads.

Cross-reference to related application This invention is an improvement over the invention described in Patent No. 3,050,328 issued Aug. 21, 1962, and assigned to the same assignee as this invention.

Background of the invention (1) Field of the Invention.The invention relates to material handling apparatus generally and to trip-release sling latch mechanisms. It also concerns sling lifting means for use with lift trucks or for use with vertical line overhead lifting means.

(2) Description of prior art.-In Patent No. 3,050,328 a single over-center trip-release mechanism simultaneously disconnected the sling halves of a pair of slings. The pair of full slings of this prior patent were spaced substantially close together and the sling apparatus was mainly useful for handling short pulpwood logs or for handling a load of substantially short material. This was particularly true when the apparatus was used in combination with a lift truck. Because the logs were lengthwise arranged correspondingly with the fore and aft axis of the lift truck, it was impractical to sling long logs. Since it is necessary to support or sling the material load as close to the front wheels of the lift truck as possible, it was impractical to support a long load of material. Also, it is frequently desirable to alternately handle long and short material loads and to readily change the sling hook-np for handling short or long loads. A further problem occurring in said prior sling apparatus resulted because of the close spacing of the pair of parallel slings; when handling a long load, the paired closely-spaced slings of said prior apparatus were necessarily arranged at the center of the load and this resulted in an unsteady load-carry; the long loads had a tendency to tilt easily and to fall or become disarranged as the load was handled.

Summary The apparatus of the present invention includes four sling halves connecta'ble in pairs to make two full slings. Each full sling includes trip means for disconnecting the lower end portions of the sling halves of that sling; the apparatus also includes linkage means for simultaneously releasing the sling halves of both full slings at the same time.

When the apparatus is in an inoperative configuration, the four slings halves hang vertically respectively from the four corners'of an oblong generally rectangular overhead frame. A hanging sling half at one corner portion of the rectangular frame is adapted to be trip-release-connected to a hanging sling half arranged either laterally or longitudinally of that sling half. The four rectangularly arranged hanging sling halves are arranged in obliquely corresponding relationship. As an example, the left rear and right front sling halves are alike and the left front and right rear sling halves are alike. Two of the alike sling halves, as for example, the left front and right rear sling halves each include two vertical cables and a link member having spaced ends pivoted to the lower end portions of the respective two cables. The link member includes a hook portion adapted to engage a loop in the end portion of either one of the other pair of sling halves; namely, the loop portion in either the left rear or right front sling half. The apparatus additionally includes jack means for pivotally raising the link member hook portion of each left and right sling half to a position to engage with the loop portion of a respective left rear or right front sling half. The apparatus additionally includes detent means selectively operable for simultaneously detaining the respective link member hook portions in engagement with the loop portions, or for simultaneously quickly releasing the link members and simultaneously disconnecting the sling halves of the pair of slings.

Brief description of the drawings FIG. 1 is a top rear perspective view of the apparatus of the invention in an inoperative configuration.

FIG. 2 is a fragmentary perspective schematic view of the apparatus illustrating the right rear sling half being connectable to either the right front sling half (shown in full lines )or to the left rear sling half (shown in broken lines).

FIG. 3 is a top schematic view illustrating the arrangement of the connected sling halves for optionally handling either a load of short logs (L) or a load of long logs (L).

FIG. 4 is a rear view of the apparatus illustrating the pivotal action of a sling half link member and also illustrating the jack and detent means for controlling the action of the link member.

FIG. 5 is an enlarged vertical sectional view taken as on the line VV of FIG. 4.

FIG. 6 is an enlarged vertical sectional view taken as on the line VIVI of FIG. 4.

FIG. 7 is an enlarged vertical sectional view taken as on the line VIIVII of FIG. 1.

Detailed description of the preferred embodiment The invention is illustrated and will be described in an embodiment adapted to be mounted on the lifting carriage structure of a lift truck and such a truck as is shown in Patent No. 3,050,328.

The tripping sling apparatus includes an oblong hori- Zontal generally rectangular frame 11 including respectively front, rear, left and right frame members 13, 15, 17 and 19. The frame includes oppositely projecting left and right cantilever portions 21, 23 projecting respectively from the left front and right rear corner portions of the frame. Base structure including a generally planar vertical baseboard 25 and left and right inclined base member 27, 29 operatively secure frame 11 to the elevatable carriage (not shown) of the lift truck.

Four oblong generally vertical sling halves including substantially alike left rear and right front sling halves 31, 33 and substantially alike left front and right rear sling halves 35, 37 are dependingly arranged respectively below the respective four corner portions of frame 11.

Left rear and right front sling halves 31, 33 each include flexible pull member means including a cable and a chain connected together. The flexible pull member means of left rear sling half 31 includes a length of cable 39 having a first latch half or loop portion 41. A length of chain 43 interconnects the upper end of cable 39 with anchor bracket 45 attached on the left rear portion of frame 11. Right front sling half 33 includes a vertical cable 47 having a first latch half or loop portion 49 formed in the lower end thereof and a vertical length of chain 51 interconnecting cable 47 with an anchor bracket 53 on the right front portion of frame 11.

Alike left front and right rear sling halves 35, 37 each include two vertical pull members and a link member: Left front sling half 35 includes a first vertical pull member 55, a second vertical pull member 57 and a second latch half or link member 59 interconnecting the lower end portions of pull members 55, 57. Link member 59 includes an oblong body portion having opposite end portions 61, 63 and a hook portion 65 projecting oblique 1y toward second portion 63. Loop portions 67, 69 formed respectively on the lower end portions of first and second vertical pull members 55, 57 permanently engage apertured end portions 61, 63 of link member 59 and pivotally interconnect the pull members and link member. Likewise, right rear sling half 37 includes first and second vertical pull members 71, 73 pivotally interconnected at the lower end portions by a second latch half or link member 75 having first and second end portions 77, 79 and a hook portion 81. Loop portions 83, of first and second pull members 71, 73 interconnect respectively with end portions 77, 79 of link member 75.

First pull members 55, 71 of left front and right rear sling halves 35, 37 are adjustably fixed respectively on the left front and right rear portions of frame 11. Lengths of chain 87, 89 connected respectively with vertical pull members 55, 71 and key-hole shaped adjustment apertures 91, 93 in frame 11 provide vertical adjustment means for pull members 55, 71.

Second pull members 57, 73 respectively are adapted to be moved up or down relative to frame 11: Upon upward movement of a respective pull member 57, 73 a respective link member 59, 75 is pivotally moved vertically about its first end portion 61, 77 and to a position with the respective hook portions 65, 81 projecting upwardly (see full line showing of link member 75 in FIG. 4). A respective link member 69, 75 is adapted to be pivotally moved downwardly as its associated pull member 67, 73 is moved downwardly and to a position with the respective hook portion 65, 81 projecting downwardly (see brokenline showing of link member 75 in FIG. 4).

The motor means of the apparatus for actuating the tripping sling halves include jack means for raising second pull members 57, 73 to up positions and detent means for detaining the pull members in up positions or releasing the second pull members to down positions. Preferably, the jack means and detent means include common structure and an over-center type lift and detent mechanical action is utilized: Left and right strut members 95, 97 are pivotally secured by bearing means 99, 101 superjacently mounted on left and right frame cantilever portions 21, 23. Each strut member 95, 97 is pivotally secured on a horizontal axis extending transversely of its cantilever frame portion 21, 23; each strut member is swingable in an are above its pivot axis and swingable through and on opposite sides of a dead center position (see FIG. 4).

Coupling means couple respectively second pull members 57, 73 of the left front and right rear sling halves respectively with the distal end portions of strut members 95, 97; U-shaped yoke members 103, 105 are interconnected respectively by bearing means 107, 109 at the upper end of the paired leg portions thereof with the distal end portions respectively of strut members 95, 97. Short lengths of chain 111, 113 interconnect respectively the upper end portions of vertical pull members 57, 73

with the medial portions respectively of the yoke members. Yoke members 103, 105 operatively invertingly straddle respectively left and right frame cantilever portions 21, 23.

Strut members 95, 97 are each arrangeable in an up or a down position respectively on opposite sides of a dead center position. First stop means in the form of paired triangular stop plates 115, 117 stop respectively left and right strut members 95, 97 in up positions. Paired stop plates 115, 117 are secured respectively perpendicularly on the inward surfaces respectively of strut members 95, 97 and engage respectively the upper planar surfaces of frame cantilever portions 21, 23 in stopping the pivotal movement of respective strut members. Second stop means in the form of resilient bumper block members 119, 121 abuttingly engage and stop respectively left and right strut members 95, 97 and stop the respective strut members in down positions; bumper blocks 119, 121 are secured respectively on the upper distal end portions of left and right frame cantilever portions 21, 23 and abuttingly engage strut members 95, 97 (see broken line showing in FIG. 4).

Linkage means interconnect left and right strut members 95, 97 for mutual corresponding movement of one strut member relative to the other strut member and for simultaneous movement of the strut members: A crossbar 123 is center-pivoted superjacently on transverse frame member 125. A left connecting rod 127 is pivotally connected at its opposite end portions respectively to left strut member 95 and one end of cross bar 123; a right connecting rod 129 is pivotally connected respectively at its opposite end portions respectively to right strut member 97 and to the other end of cross bar 123. A preferred structure for pivotally attaching the respective end portions of connecting rods 127, 129 with strut members 95, 97 includes pin means 131, 133 extending respectively through paired triangular stop plates 115, 117.

Selectively operable actuating means is operatively connected with the linkage means of the apparatus for selectively simultaneously pivotally moving strut members 95, 97 to either up or down positions: The actuating means preferably includes a piston-cylinder assembly 135 shiftably coupled between frame 11 and cross bar 123. The piston rod distal portion of piston-cylinder assembly 135 is interconnected by swivel bearing 137 with cross bar 123', the base end of the cylinder of assembly 135 is shiftably mounted from frame 11. Contra-directionally operative sliding base means including a slideway rod 139 and a base block 141 rectilinearly slidably secure the base end of piston-cylinder assembly 135 from frame 11. Annular support members 143, 145 are concentrically fixed respectively on the right and left end portions of slideway rod 139 and in turn are fixed in spaced arrangement superjacently on real frame member 15. Bottom surface 147 of base block 141 slidably rides on the upper surface of frame rear member 15 and prevents pivotal movement of base block 141 about slideway rod 139. A pivot pin 149 extending through paired upright boss portions 151 of base block 141 pivotally interconnects the base block with the base end of cylinder assembly 135. Selectively directable pressurized fluid moves respectively through conduits 153, 155 in cylinder assembly 135 for extending or contracting the cylinder assembly. Right and left annular support members 143, 145 provide confrontingly arranged right and left limiting surfaces 157, 159 (see FIG. 4). Base block 141 is adapted to abut left limit surface 159 when cylinder assembly 135 is extended and the strut members are moved to down positions.

Sling halves 31, 33, 35, 37 are optionally adapted to be connected together to form a short-spaced parallel pair of full slings or connected to form a long-spaced parallel pair of full slings. The paired full slings are adapted to be arranged a short distance apart for handling short logs or adapted to be arranged a relatively long distance apart for handling long loads; a sling half hanging from one corner of frame 11 is adapted to be connected with either a longitudinally or a transversely spaced sling half (see FIGS. 2 and 3).

The following procedure may be carried out in slinging a load of short logs (indicated L and shown in full lines in FIG. 3): The lift truck is positioned so that frame 11 is arranged transversely of and directly over the load of short logs L to be handled; With the carriage of the lift truck in a lowered position, and strut members 95, 97 of the tripping sling apparatus in up positions, left rear and right rear sling halves 31, 37 are connected and left front and right front sling halves 35, 35 are connected; loop portion 41 of left rear sling half 31 is passed under the load of short logs and connected with link member hook portion 81 of right rear sling half 37, Likewise, loop portion 49 of right front sling half 33 is passed under the load of short logs and connected with link member hook portion 65 of left front sling half 35; the load may be then lifted and transported to a desired location; To trip-release the load of short logs, the operator actuates cylinder assembly 135 to an extended disposition; as assembly 135 is extended, strut members 95, 97 simultaneously move past dead center positions and in turn link members 59, 75 pivot about their first end portions 61, 77; the pivoting action of the link members disengages hook portions 65, 81 respectively from loop portions 49, 41, of right front and left rear sling halves 33, 31 and releases the load.

It will be noted that during the heretofore described operation, base block 141 sliding on rod 139 provides an instant or mid-air trip feature once the yoke members 103, 105 have passed over center. In other words, the block 141 merely has to follow cylinder assembly 1335 rather than the pump (not shown) having to afford the amount of oil necessary to keep the cylinder of cylinder assembly 135 full when the yoke members 103, 105 have passed over center.

For handling a load of long logs (indicated L and shown in broken lines in FIG. 3), the following procedure may be carried out: The lift truck is arranged with frame 11 lengthwise with and directly over the load of long logs L to be lifted; the carriage of the lift truck is lowered, and sling halves 31, 35 and 33, 37 are connected; Cable 39 of left rear sling half 31 is passed under the load of long logs and loop portion 41 is connected with hook portion 65 of left front sling half 35; likewise, cable 47 of right front sling half 33 is passed under the load and loop portion 49 is connected with link member hook portion 81 of right rear sling half 37; the load of long logs is lifted, transported and released in substantially the same manner as above described for handling short logs.

Although the present invention has been described with reference to a preferred embodiment thereof, it is to be understood that it is not to be so limited since changes and modifications may be made therein which are within the full intended scope of this invention, as hereinafter claimed.

I claim:

1. Tripping sling apparatus for use with powered lifting means having a lifting structure, said apparatus comprising an oblong horizontal frame operatively secured to said lifting structure, four oblong generally vertical sling halves attached to said frame and hanging from four generally rectangularly arranged places on said frame, said sling halves including substantially alike left rear and right front sling halves and substantially alike left front and right rear sling halves, said left rear and right front sling halves each including a vertical flexible pull member fixed at its upper end on said frame and a first latch half attached at its lower end, said left front and right rear sling halves each including a first and a second vertical flexible pull member and a second latch half means for connecting with a first latch half on said left rear sling half or on said right front sling half, said first pull member of said left front and said right rear sling half being fixed at its upper end on said frame and being connected at its lower end to a said second latch half for the unlatching of said second latch half from said first latch half, said second pull member of said left front and right rear sling half being adapted to move to an up or a down position relative to said frame and selectively operable rnotor means for raising and simultaneously holding said second pull members of said left front and said right rear sling halves in an up position or for simultaneously releasing said second pull members for simultaneous movement of said second pull members to a down position; when said scond pull member of each said left front and said right rear sling half is in an up position said second latch halfmeans thereof being adapted to be optionally connected'with a selected first latch half of said left rear or right front sling half; the second latch half means of a left front or right rear sling half being adapted to be engaged with the first latch half of a left rear or right front sling half for forming one of two load-bearing slings of the apparatus; the tripping sling apparatus being operative to releasably sling an oblong load of material belowand optionally lengthwise or crosswise relative to said frame by optionally connecting selected sling halves together and by forming a parallel spaced pair of slings optionally spaced apart either lengthwise or crosswise relative to said oblong frame.

2. Tripping sling apparatus for use with powered lifting means having a lifting structure, said apparatus comprising an oblong horizontal frame operably secured to said lifting structure, four oblong generally vertical sling halves attached to said frame and hanging from four generally rectangularly arranged places on said frame, said sling halves including substantially alike left rear and right front sling halves and substantially alike left front and right Wear sling halves, said left rear and right front sling halves each including a vertical flexible pull member fixed at its upper end on said frame and having attached at its lower end a loop means, said left front and right rear sling halves each including a first and a second vertical pull member and a link member, said link member including an oblong body portion having first and second end portions and a hook portion arranged medially of said end portions and projecting obliquely towards said second end portion, means pivotally securing respectively the first and second end portions of said link member body portion respectively with the lower end portions of said first and second pull members, said first pull member of said left front and said right rear sling half being fixed at its upper end on said frame, said second pull member of said left front and right rear sling half being adapted to be moved to an up or a down position relative to said frame, said link member of said left front and right rear sling half being movable vertically about its first end portion to an up position wherein said link member second end portion is pivoted upwardly with said hook portion projecting upwardly or said link member being pivotally movable downwardly under force of gravity about its first end portion and to a down position wherein said link member second end portion is pivoted downwardly with said hook portion projecting downwardly, jack means for raising said second pull members of said left front and right rear sling halves and detent means selectively operable for detaining said second pull members simultaneously in up positions or for simultaneously quickly releasing said pull members to down positions 3. The apparatus of claim 2 wherein said jack means and said detent means include common structure including a left and a right strut member pivoted each at one end thereof on a horizontal axis on said frame, each strut member .being swingable in an are above said pivot axis and swingable through and on opposite sides of a dead center position, left and right coupling means coupling respectively the second pull members of said left front and right rear sling halves respectively to the distal end portions of said left and right strut members, first stop means for stopping each strut member in an up position and such position wherein the strut member is arranged slightly on one side of said dead center, second stop means for stopping each strut member in a down position and such position wherein the strut member is arranged on a side of said dead center opposite from the up position arrangement of said strut member, linkage means interconnecting said left and right strut members for mutual corresponding movement of one strut member relative to the other strut member and for simultaneous movement of the strut members, and selectively operable actuating means operatively connected with said linkage means for selectively simultaneously pivotally moving said strut members to either up or down positions.

4. The apparatus of claim 3 wherein said frame includes oppositely projecting left and right cantilever portions and wherein said left and right coupling means include respectively left and right U-shaped yoke members each being pivoted at its upper end paired leg portions on a horizontal axis to the distal end portion respectively of a left or right strut member and each yoke member being connected at its lower center portion with the upper end portion of a respective second pull member and further with said left and right yoke members operatively invertingly saddling respectively said left and right frame cantilever portions.

5. The apparatus of claim 3 wherein said linkage means includes a cross bar pivoted at its center on said frame, a left connecting rod, its opposite end portions pivoted respectively to said left strut member and to one end of said cross bar, a right connecting rod, its opposite end portions being pivoted respectively to said right strut member and to the other end of said cross bar.

6. The apparatus of claim 5 wherein said actuating means includes a contra-directionally operative fluidpowered piston-cylinder assembly having a piston rod operatively connected with said cross bar and additionally includes contra-directionally operative sliding base means including a slideway mounted on said frame, a base block pivotally connected with the cylinder base of said pistoncylinder assembly and rectilinearly slidably secured on said slideway, and contra-directionally operative right and left limit means arranged respectively at the opposite end portions of said slideway for limiting the contra-directional movement of said base block; said base block being adapted to abut said right limit means when said pistoncylinder assembly is contracted and said strut members are arranged in up positions; said base block being adapted to abut said left limit means when said piston-cylinder assembly is extended and said strut members are arranged in down positions.

References Cited UNITED STATES PATENTS 2,927,815 3/1960 Flatau 29476 3,039,809 6/1962 Eaves 294-76 3,050,328 8/1962 Eaves 29476 EVGN C. BLUNK, Primary Examiner.

H. C. HORNSBY, Assistant Examiner. 

